fall这是什么意思

例句：

She broke her right leg in a bad fall.

她在一次严重的`跌倒中右腿骨折了。

They announced a fall in pretax profits.

他们宣布了税前利润的下降。

Large flakes of snow began swiftly to fall.

大片大片的雪花开始飞快地落下。

House prices could perk up during the fall.

秋季房价可能会上涨。